I have an spare BBB, and I can test this if you send me an image + test case. I'm not setup for building images right now.
The code looks correct, sans all the type changes. I'd recommend committing the type changes separately from fcmpset change.

The BBB has an armv7 CPU so it uses atomic-v6.h, not this file. Only a few specific armv4/v5 boards are supported by FreeBSD and they aren't the common BBB, ${FRUIT}Pi type boards which are all based on armv6 (original RPi) or armv7/v8.

I have an spare BBB, and I can test this if you send me an image + test case. I'm not setup for building images right now.
The code looks correct, sans all the type changes. I'd recommend committing the type changes separately from fcmpset change.

The BBB has an armv7 CPU so it uses atomic-v6.h, not this file. Only a few specific armv4/v5 boards are supported by FreeBSD and they aren't the common BBB, ${FRUIT}Pi type boards which are all based on armv6 (original RPi) or armv7/v8.

armeb is in danger, since there were almost no responses to my call for users.
armv4,5 is less in danger since there were responses. There's users, but the floor for FreeBSD is rising and may rise above what they can provide.